Mannoproteins are mannans bound to proteins which are found in particular in yeast walls where they have a structural and/or antigenic function.
Mannoproteins are commonly used in oenology, in particular for stabilizing wine (see for example documents WO 96/013571, WO 01/046380 and WO 06/067147). The use of mannoproteins for reducing the haze level of alcoholic beverages is described in application WO 07/034986.
In patent application EP 0 790316, mannoproteins are used as an emulsifier in beverages and food products.
In the application WO 01/066574, the mannoproteins of cryptococcus neoformans are used for the preparation of a medicament intended for the treatment of inflammatory diseases or infections, via a method of administration by systemic route. The mannoproteins then make it possible to suppress neutrophil migration.
Moreover, mannoproteins are described as an adjuvant of active ingredients, i.e. as a compound making it possible to improve or reinforce the therapeutic effect of active ingredients.
Thus, in international application US 2005/0226822, mannoproteins are used as ovomucin adjuvants in oral care compositions.
International application WO 06/036817 describes the use of mannoproteins as an adjuvant in a pharmaceutical composition comprising fungal cells or cell extracts genetically modified so as to have at least one altered filamentation property. The immunogenic properties of the mannoproteins are used to improve the immune response of the composition. This application is based on a principle of vaccination against fungal infections due in particular to fungi of the genus Candida. 
In patent application US 2005/0191268, mannoproteins are used as polyphenol adjuvants in cosmetic preparations comprising an extract of a residue of the winemaking process and one or more cosmetic additives or adjuvants. Said residue is the deposit remaining at the bottom of the vats after the wine is pumped out on completion of fermentation. Said residue extract comprises one or more polyphenols and one or more proteins, for example mannoproteins, as association complexes.
In the cosmetic field, it is useful to have multi-functional agents which make it possible in particular to reduce the range of raw materials necessary for the preparation of different cosmetic compositions and/or to simplify the method for preparing the cosmetic products.
Furthermore, consumers are in search of natural cosmetic products, comprising components of natural origin. It is therefore useful to have natural functional agents for preparing cosmetic products.